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Open in CAN Main Bus Line





NETWORKING: CAN COMMUNICATION SYSTEM: Open in CAN Main Bus Line
- Open in CAN Main Bus Line

DESCRIPTION

There may be an open circuit in one of the CAN bus main wires and/or a DLC3 branch wire when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 70 Ohms or higher.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* Turn the power switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
* Turn the power switch off before inspecting CAN bus wires for a ground short.
* After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
* Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

HINT
* Operating the power switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
* Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE

1. CHECK FOR OPEN IN CAN BUS WIRE (DLC3 BRANCH WIRE)

(a) Turn the power switch off.

(b) Measure the resistance according to the value(s) in the table below.





Standard Resistance:





Text in Illustration





NOTICE:
When the measured value is 133 Ohms or higher and a CAN communication system DTC is output, there may be a fault besides disconnection of the DLC3 branch wire. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area How to Proceed With Troubleshooting.

NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3
OK -- Continue to next step.

2. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM)

(a) Disconnect the ECM connector.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (POWER MANAGEMENT CONTROL ECU)

OK -- REPLACE ECM Removal

3. CHECK FOR OPEN IN CAN BUS MAIN WIRE (POWER MANAGEMENT CONTROL ECU)

(a) Reconnect the ECM connector.

(b) Disconnect the power management control ECU connector.





(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 1 J/C)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 1 J/C)

(a) Reconnect power management control ECU.

(b) Disconnect the CAN No. 1 junction connector.





(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 1 J/C - POWER MANAGEMENT CONTROL ECU)
OK -- Continue to next step.

5. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 1 J/C - CAN NO. 2 J/C)

(a) Measure the resistance according to the value(s) in the table below.





Standard Resistance:





Text in Illustration





NG -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 2 J/C)

OK -- REPLACE CAN NO. 1 JUNCTION CONNECTOR

6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 2 J/C)

(a) Reconnect the CAN No. 1 junction connector.

(b) Disconnect the CAN No. 2 junction connector.





(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





Result:





B -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 2 J/C - ECM)

C -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 1 J/C - CAN NO. 2 J/C)

A -- REPLACE CAN NO. 2 JUNCTION CONNECTOR